Why have some scientist referred to fossil fuels as ancient sunlight?

Question

why is using ancient sunlight to fuel our current energy needs a problem? what alternatives do we have? what problems will we encounter if we don't change our behavior? what changes do you think will be the most important for us to make at this time in our history?

Answer 1

Fossil fuels, meaning coal, petroleum, and natural gas were all made from the remains of plants and animals that lived hundreds of millions of years ago.  The plants collected the sunlight and used it to form carbohydrates.  The animals ate the plants and used the carbohydrates to make fats.  The bodies of the plants and animals were buried and covered with sediments which accumulated over millions of years, and the fats and carbohydrates were transformed by geologic processes into concentrated carbon in coal and liquid and gas hydrocarbons.  When we burn these, we are using the energy of the sunlight that fell on earth eons ago.

The problem is that we burn it up millions of times faster than it can be created.  Although coal and oil are still being created by the same processes, it will take hundreds of millions of years to replace the amount that we burned up in the last century.  So for all practical purposes, they are irreplaceable.   At some point we have to run out, and in the case of oil, that point appears to be in sight.

The second problem is that there are no good alternatives.  Fossil fuels are highly concentrated sources of energy, and they are relatively easy to get.  You just dig them or pump them out of the ground and do some refining to clean out the impurities.  Nothing else is as concentrated or as easy to obtain.

The third problem is that burning carbon and hydrocarbons results in huge amounts of carbon dioxide, along with a lot of other pollutants.  Although we have found ways to clean up a lot of the pollutants, there is no good way to get rid of the  carbon dioxide, and it is accumulating in the atmosphere to the point where it is causing global warming.

The most important change we need to make is to stop burning fossil fuels and find some renewable source of energy to keep our energy dependent civilization alive.

Answer 2

Cutesy name.  Coal is made from dead plants and trees that have been compressed under a millions of years of , time, heat, and pressure and dirt.  Sun once shinned on the leaves.

Sort of like Global Warming is now called Climate Change.